The U.S. State Department Thursday released its annual report that grades foreign governments on their efforts to fight human trafficking, but activist groups say they are concerned that some countries' rankings are politically influenced.

Much attention is focused on the upgrade of Thailand from Tier 3 to the Tier 2 Watchlist in the Trafficking in Persons (TIP) Report.

Thailand has been at the center of a region traditionally rife with trafficking syndicates aided by complicit and corrupt officials. In recent years, investigations have found trafficked and enslaved workers in the country's billion-dollar seafood industry.

The U.S. ambassador to Thailand, Glyn Davies, said the country's ranking reflects its improvements. "Thailand has made some great progress that we should all applaud over the past year," he said.

In a statement released Thursday, the U.S. embassy said that in 2015, the Thai government reported increased investigations into sex trafficking cases and suspected cases of forced labor in the fishing industry as well as the convictions of "hundreds of traffickers." Despite those improvements, the embassy also said that most complicit officials, employers and brokers involved in trafficking continue to operate with relative impunity.

However some activists disagree that Thailand's efforts merit an upgrade.

“The conditions are worsening in that country for migrant workers,” said Kristen Abrams, director of the Alliance to End Slavery & Trafficking (ATEST). “There continues to be egregious labor abuse, particularly in the seafood industry. We believe that Thailand should stay on Tier 3.”

The TIP report ranks nations on a three tier system. Tier 1 includes countries whose governments fully comply with minimum standards. Tier 2 countries are not in full compliance with the minimum standards, but are making significant efforts to comply.

The lowest ranking is Tier 3, which includes countries whose governments do not fully comply with the minimum standards and are not making significant efforts to do so. A Tier 3 ranking is not only an international badge of shame but it can trigger sanctions limiting access to aid from the United States and other countries.

Malaysia, a destination country for many of those trafficked, as well as for Rohingya fleeing Myanmar, was moved up from Tier 3 to the Tier 2 Watch List in the 2015 TIP Report.

“Malaysia absolutely should be downgraded to Tier 3,” Abrams told VOA, alleging last year's upgrade was linked to negotiations with the U.S.-led Trans Pacific Partnership trade pact. “It would be unjustified today to keep them on the [Tier 2] watch list.”

Uzbekistan is another country activists suspect U.S. officials have kept off the blacklist for diplomatic considerations.

Senior U.S. diplomats repeatedly overruled the State Department’s anti-trafficking unit and inflated the grades of 14 strategically important countries, according to a Reuters report last August.

The State Department denied political factors in formulating its principal diplomat tool to engage foreign governments on human trafficking, but U.S. lawmakers called for the process to be reformed.

“TIP and its associated sanctions are actually reasonably effective tools when it comes to governments that value their relationship with the U.S.,” Sam Zarifi, Asia regional director for the International Commission of Jurists, told VOA.

Abrams of ATEST in Washington said the U.S. government has taken some very positive steps to combat human trafficking, but added “if the State Department is going to let political influences impact the report and see that this report is not released with integrity that is going to call the Obama administration's legacy into question.”

The grassroots Migrants Workers Rights Network, which claims 4,000 members in Thailand and Myanmar, said it supports an upgrade for Thailand, noting “significant improvements” but cautioning there is still a “long way to go.”

MWRN also voiced approval of the expected downgrade for Myanmar to Tier 3. Andy Hall, an advisor to MWRN told VOA there were, “little positive moves under the former government” and there “are still major problems and not enough progress” on the issue of human trafficking.

Human rights groups have criticized the Thai junta’s closure of borders to thousands of survivors of trafficking who were at risk of death at sea and it detained others in what activists characterized as inhumane conditions.

“It is our national agenda to end human trafficking,” deputy prime minister Prawit Wongsuwan, a retired army commander-in-chief, told reporters on Wednesday.

“We’ve done much better than in previous times,” said Thai prime minister Prayuth Chan-ocha earlier in the week.

Prayuth, who as Army chief two years ago led a bloodless coup to oust civilian leaders, has used his sweeping powers to try to reduce trafficking in the kingdom.

Actions have included shuffling officials, deemed as complicit or not doing enough to combat trafficking, and improving legal procedures.

“The U.S. is trying to edge its relationship with Thailand back into the light and also rewarding some of the Thai government's efforts over the last year,” Zarifi said of Thursday’s expected upgrade for the kingdom.

Myanmar, also known as Burma, was demoted to Tier 3 to prod it to do more to curb the use of child soldiers and forced labor and amid the continuing widespread persecution of Rohingya Muslims in the Buddhist-majority country. That would place the country alongside Iran, North Korea and Syria as among the worst human trafficking states.

“Of course we will be disappointed [with a downgrade] as we’ve been working with all the parties” to improve the situation, Aung Lin, the permanent secretary at the Ministry of Foreign Affairs told VOA.

“We are doing our job and will continue to do it,” the official added.

After decades of military rule Myanmar now has a democratically elected government led by Aung San Suu Kyi as state counselor, although the military — her traditional nemesis, remains powerful.

Aung San Suu Kyi has faced criticism since last year’s overwhelming victory of her National League for Democracy (NLD) for not doing enough regarding the plight of the Rohingya.

Myanmar’s government refuses to use the word “Rohingya,” regarding the ethnic group as Bengalis who are illegal immigrants from Bangladesh.